Page 107 - Materials Chemistry, Second Edition

5.2 The environmental assessment—LCA 103
2005; Funazaki et al., 2003; Park et al., 2003; Chevalier et al., 2003; Shiels et al., 2002). The
main content aims to:

(1) formulate environmental policy and international management system, coordinate the
regional or global environmental problems, improve and protect environment by
standard ways, and satisfy the needs of sustainable development of economy;
(2) establish environmental product standard and implement ecolabelling plan;
(3) formulate corresponding tax, credit, investment, and environmental protection policy,
and accelerate the development of the industry of waste recovery and recycling;
(4) optimize energy, transportation, and waste management solutions of government,
minimize the environmental load and economic cost of the economic system; and
(5) provide the public with information about the related products and raw materials,
improve ecological consumption benchmarks, and advocate green and sustainable
consumption.

5.2.4 Limitation
Though the technical framework and analysis features of an LCA have also been widely
accepted and understood, there is no consensus on the specific operation. Therefore, LCA
faces many complications, as exhibited in the definition of system boundary, the definition
of the impact categories, the choice of the impact evaluation models, and so on. As far as eval-
uation methods are concerned, some defects remain in current impact evaluation models and
integration methods.

5.2.4.1 Objective problems
It is almost impossible for life cycle assessment to avoid the influence of subjective factors,
which is determined by the understanding of the LCA method, the knowledge of the system
evaluated, the knowledge background, and the value judgment of the executors of an LCA
(Huijbregts, 1998; Owens, 1996). For example, in one respect, the choice of the system bound-
ary depends on the cognition degree of the object of the study and the predetermined research
target. In another aspect, when quantificationally evaluating an impact type, several kinds of
models can be used to determine the effect. Different models can offer different results, some
of which can be measured in orders of magnitude. Thus, artificial selections of impact assess-
ment models make the evaluation results subjective.

5.2.4.2 Limitations of information and data
ForLCA,thelimitationsofinformationanddataareoneofthemajorhindrances(Ciroth,2004;
Rossetal.,2002).Thishindranceappearsintwoaspects:lackofinformationwhichcanbeusedas
influencecategorybasis,andlackofinformationanddatafromeachstageoftheLCA.Itisusually
hard to obtain the related data and the data gained is of low quality. The typical production pro-
cess or the mean level are adopted as the substitutes. The data may be estimated by empirical
formulas (or experience judgment); this means that the data may be inaccurate and the error
maybebigger,whichcouldbemisleading.Itisalsonoteasytosolvetheproblemsabove.Inorder
to solve the problems, the mining industry, the raw material production industry, and the prod-
uct manufacturing industry should work together, effectively.